package com.yun.filterdemo;

import javax.servlet.*;
import javax.servlet.annotation.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;

@WebFilter(filterName = "AuthFilter", urlPatterns = "/test1/*")
public class AuthFilter implements Filter {
    public void init(FilterConfig config) throws ServletException {
    }

    public void destroy() {
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws ServletException, IOException {
        HttpServletRequest req = (HttpServletRequest)request;
        Object obj = ((HttpServletRequest) request).getSession().getAttribute("username");
        String path = req.getServletContext().getContextPath();
        HttpServletResponse res = (HttpServletResponse)response;
        if (obj == null){
            res.sendRedirect(path+ File.separator+"login.jsp");
            return;
        }
        chain.doFilter(request, response);
    }
}
